1. Field of the Invention
The present invention is related to an apparatus and process for cleaning endoscopic surgical instruments by flushing the cannula. More particularly, the present invention is directed to a hand-operated apparatus for forcing a cleaning solution through an endoscopic cannulated surgical instrument to remove gross debris from surgery that utilizes a syringe or other source of pressurized cleaning solution to provide the motive power required for forcing a cleaning solution through the cannula of an endoscopic cannulated instrument. In a preferred embodiment, the present invention includes pressurized tanks for delivering a steady flow of flushing solutions through an endoscopic cannulated instrument.
2. Description of Related Art Including information Disclosed Under 37 C.F.R. Sections 1.97-1.99
Increasingly, surgeries are conducted with endoscopic cannulated instruments, or instruments, which are inserted through minimal surgical openings in the body to reduce the invasiveness of surgical procedures. Endoscopic instruments are long instruments having a narrow elongated sleeve or housing with cables, rods and the like being threaded through them and connected to tools on the working, or distal, end that are manipulated by squeezing scissors-like handles, or other control mechanism, on the other, proximal end, which remains outside the patient. Many endoscopic instruments have a rigid outer housing and a rod reciprocates inside the housing to actuate a surgical tool on the distal end of the endoscopic instrument. Other endoscopic instruments are flexible and are used primarily in conjunction with a cannulated endoscope. For purposes of this disclosure, an endoscopic instrument includes all instruments used in minimally invasive surgery and having an elongated housing or sleeve that forms a cannula that houses any type of control mechanism, e.g., rod or cable, to control a tool or instrument for use inside a patient's body. The present invention is directed to an apparatus for cleaning gross debris from any such type of medical instrument by flushing the cannula.
All these instruments are cannulated instruments, that is, each has an elongated cannula, which is almost completely filled with instrument and controls. It is the cannula that traps gross debris, which is invariably drawn into the cannula when the control rods, wires, and the like reciprocate within the cannula formed by the outer housing or sleeve of endoscopic instruments.
During use, endoscopic instruments draw bodily fluids and tissues and other matter from the patient, known collectively as "gross debris," into the elongated tubular housing of the endoscopic instrument. These tubes are quite small and most of their volume is filled with the control rod or the like, leaving little room for cleaning. The sleeve or housing of endoscopic instruments are not sealed, and the reciprocal movement of the inner workings within the sleeve invariably draws gross debris into the sleeve, from which it cannot be removed effectively using devices currently known in the medical profession. Further, surgeons operating inside the abdominal cavity pressurize the abdominal cavity with carbon dioxide to separate organs and tissues from one another and this pressurized gas leaks through cannulated instruments, forcing gross debris into the housing of the endoscopic or cannulated instruments.
Because there is virtually no way to disassemble reusable instruments, they tend to trap blood, other fluids, and tissue in the space between the tool control rod and the housing. This gross matter inhibits the ability of pressurized steam, ethylene oxide or chemical sterilants to effectively reach all parts of the instrument. Further, the space between the housing and the instrument control rod typically harbors spores, which are not killed by enzymatic cleaners, but can only be killed by steam or appropriate gas, such as ethylene oxide. Gross debris, however, frequently covers spores or surrounds them, reducing the efficacy of either steam or ethylene oxide to reach and kill them. This may allow spores or other blood-borne pathogens to survive inside the housing, greatly increasing the risk of patient infection from cross contamination from other patients. Even if it were possible to disassemble cannulated instruments for thorough cleaning, it would be prohibitively expensive and time consuming to do so.
Endoscopic instruments are cleaned and sterilized according to hospital protocol, which varies widely between institutions. In some cases, endoscopic instruments are sterilized during the night, in a process that takes about at least 30 minutes. During the day, however, they may be repeatedly used for consecutive surgeries on different patients with minimally accepted cleaning and sterilization practices, partly because hospital staff cannot afford to take the time required for complete sterilization. With the increase of endoscopic procedures and lack of proper cleaning techniques, gross debris build up is probable and potentially widespread. In the age of AIDS, and contagious hepatitis type B, this situation is obviously of great concern, which has been recognized, but not solved, by the medical community.
Currently about 2.2 million surgical procedures employing endoscopic instrument are performed each year. It is estimated that by the year 2000 more than one-half of all surgeries will performed with minimally invasive techniques, that is, with endoscopic instrument, which will be about 11 million surgeries per year. The potential for serious cross-contamination between patients and resulting transmission of disease is clear, but no clear, effective and affordable solution to the problem is known.
Some approaches to addressing the problem of removing gross debris from the exterior of endoscopes, which are tightly sealed and do not admit debris, as they have no cannula, have led to issued patents, some of which are discussed below. No issued patents specifically directed to removing gross debris from the cannula of endoscopic cannulated instruments, however, have been located.
U.S. Pat. No. 4,667,691, issued to Sasa on May 26, 1987 (Sasa '691), discloses a "Device for Cleaning channels of an Endoscope" comprising syringe provides the power to force a liquid cleaning solution through an endoscope through a complex series of valves and tubing. The fluid flows first through a main body, into which it is drawn from a fluid storage tank and from which it is forced into the tubing, other valves, and the endoscope and so forth.
U.S. Pat. No. 4,525,220, issued to Sasa et al. on Jun. 25, 1985 (Sasa et al. '22), discloses a "Method of Cleaning Endoscope Channels" comprising a number of methods of using the device disclosed and claimed in Sasa '691, which is described above.
U.S. Pat. No. 4,439,884, issued to Giorni on Apr. 3, 1984 (Giorni '884) discloses a "Container with Bristles for Cleaning Instruments" comprising a cylindrical vessel with an open top. A plurality of bristles project horizontally and inwardly from the inside side wall toward the center of the vessel. The vessel is filled with an appropriate cleaning fluid. The instrument is submerged in the fluid and is rotated by hand to clean it. If desired, the instrument may be supported by a ring 9 connected to a clamp 10 on the outside of the vessel.
U.S. Pat. No. 4,288,882, issued to Takeuchi on Sep. 15, 1981 (Takeuchi '882), discloses an "Endoscope Sheath Cleaning Device" comprising a bulky free-standing machine having a J-shaped tube into which an endoscope sheath is inserted progressively and repeatedly, either by hand or machine, while water or other solution is sprayed on it from two opposed nozzles located near the top of the apparatus. The spray from the nozzles is directed downward onto a brush set which brushes the exterior of the sides of the endoscope. It does not appear that any fluid is forced through the endoscope by this apparatus.
U.S. Pat. No. 4,281,646, issued to Kinoshita on Aug. 4, 1981 (Kinoshita '646), comprises a window washer for cleaning the observation window at the end of an endoscope having an observation window, while the endoscope is in use.
None of these devices is directed to removing gross debris from the cannula of endoscopic cannulated surgical instruments in general. Moreover, none of these devices offers an inexpensive, disposable and reliable endoscopic cannulated instrument cleaning apparatus for removing gross debris from the cannula that is also simple, convenient and easy to use and to manufacture. Further, none of these devices offers a comprehensive system for cleaning a large number of instruments without stopping for additional flushing solutions. Therefore, a serious need exists for an endoscopic cannulated instrument cleaning apparatus that is inexpensive, disposable and reliable, while also being simple, convenient and easy to use and to manufacture and that allows for cleaning a large number of instruments without stopping for additional flushing solutions. Such an apparatus is disclosed and claimed in this document, as follows.